2x/3+3y/4=17/12 x/6-y/2=-1/3

把(x-y)看作一个整体,化解:5(x-y)+2(x-y)-4(x-y)= 3(x-y)把(x-y)看作一个整体,化解:5(x-y)+2(x-y)-4(x-y)=3(x-y)²-4(x-y)+7(x-y)-6(x-y)²= x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20 {(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20 4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6 {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 （x+y）/2- x-y/2=6 3(x+y)=4(x-y) x+y/3+x-y/2=6 4(x+y)-2(x-y)=40 初二上学期方程题 4x+y=5 5x+4y=63x-2y=1 2x+3y=13x-2y=7 7x+5y=32x+3y=17 2x-y=-4x+5y=6 2x+y=23x-6y=4 3x+2y=52x+y=73x-4y=53x+y=1x-2y=-1x+y=42x+3y=92x-3y=74x+5y=3x+y=20004x+6y=90003x+5y=113x-2y=42x+3y=215x-2y=5x+y=54x+3y=182x+3y=16x+4y=132x+3y=40x 解方程组：x+y/2+x-y/3=6 4(x+y)-5(x-y)=12 解方程组{2(x-y)/3 - x+y/4=-1 6(x+y)-41(x-y)=12 8（x-y)=3（x+y)-12 6（x+y)=4（2x-y)+16 8（x-y)=3（x+y)-12 6（x+y)=4（2x-y)+16 2X-3Y=12 3X-4Y=17加减消元法3x+2y=94x-2y=52x-3y=123x-4y=175x-5y=715x+20y=72x+3y=56x-5y=-6 (x-y) (x-2y)+(x+2y) (x-3y)-2(x-3y) (x-4y)= 求值域 1,y=(x+2)/(x*x+3x+6) 2,y=3x/(x*x+4) 若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 [(x+2y)²-（x+y)(3x-y)-5y²]÷(2x),其中x,y满足x²+4x+y²-y+17/4=0已知、x+y=6且xy=4(1)x²+y² (2)（x-y）² (3)x{四次方}+y{四次方}第一题没错 书上就这样写的！ 计算：1.y/4x²-1/12y²+1/6xy 2.3/x-6/1-x-x+5/x²-x3.x/x-y×y²/x+y-x四次方y/x四次方-y四次方÷x²/x²+y²解方程：1.x-1/（x-2）+1=1/2-x2.x+1/x-1-4/x²-1=13.1/x+3-2/3-x=1/x²-9